I work on cars. AMA

[Anonymous]

Anonymous wrote:Have you ever known a technician who intentionally damaged a car that was in the shop for work? If so, what was their motivation?

Yep. Sometimes it was to run up billable hours for more work on the current visit, create a future failure/more work, or just being a prick. It happens. People suck.

[Anonymous]

Hi. I have 2011 Mercedes ml350 4matic suv that has just over 200000 miles. When I go up hills and or accelerate at slower speeds (less than 40mph), the car stutters and kind of hesitates. A friend riding with me said it seems like a transmission issue. I haven’t taken it to the shop yet but how much more would you invest in a car with that type of mileage? The car has been pretty good to me. However, last year I spent $1000 to get A/C repaired (cracked compressor) $270 lift gate repair and $300 for window motor. I really wanted to keep it for my nearly 17 year old DD but I wondering should I just move on? I would love to move up to a 2015/2016 GL but my current mechanic thinks those are trash and constantly trying to talk me into buying a Honda Pilot or something Korean. Any recommendations or general thoughts?

Also wondering what are the service recommendations when car hits 200000 miles?
TIA!

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:You mentioned you go to Carlisle for the auction a lot. What are the pickings like there? I've traded in a few cars to dealers a few times, and my impressions was they keep the good ones for their own used car lot, and send all the bad stuff up to auction.

Yeah, that’s about right. The stuff at auction needs attention. Used dealers or wholesalers don’t wanna mess with a car they have to fix before selling. That’s a waste of money them. They don’t even staff a technician at most used dealers.

Which is why I buy at auctions. Because I can pay almost nothing for a car, literally like $50 more than scrap value sometimes, spend a few days fixing it, and turn at least a couple thousand dollars on it most of the time. The downside is I spend a lot of time waiting on UPS to drop parts off, and I have a lot of cars sitting on my property in various stages of repair, but my wife doesn’t mind. One of the benefits of having a big lot with a tall privacy fence.

Could you please provide some more info about the Carlisle auction lot, city location, name of company (Mannheim?) and how best to be able to purchase a car from there? I believe one needs to go via a person of company licensed to purchase at car auctions, correct? I do small repairs on car myself so thought I'd take the risk getting a car from an auction.

You’d be better off going to Gettysburg. They run a great auction that is very friendly to the public. The rules are a little complicated sounding at first, but you’ll figure it out. They auction of Thursday’s I believe. Manhien will want your dealer license, tax ID, and shipper info. Not as friendly to the public as Getty. Carlisle is mostly classics, specialty, and hot rods. I go for the hot rods.

[Anonymous]

Anonymous wrote:Hi. I have 2011 Mercedes ml350 4matic suv that has just over 200000 miles. When I go up hills and or accelerate at slower speeds (less than 40mph), the car stutters and kind of hesitates. A friend riding with me said it seems like a transmission issue. I haven’t taken it to the shop yet but how much more would you invest in a car with that type of mileage? The car has been pretty good to me. However, last year I spent $1000 to get A/C repaired (cracked compressor) $270 lift gate repair and $300 for window motor. I really wanted to keep it for my nearly 17 year old DD but I wondering should I just move on? I would love to move up to a 2015/2016 GL but my current mechanic thinks those are trash and constantly trying to talk me into buying a Honda Pilot or something Korean. Any recommendations or general thoughts?

Also wondering what are the service recommendations when car hits 200000 miles?
TIA!

Congrats on getting your car to 200K. Well done. I’ll admit I don’t know much about MB’s, they’re not my area of expertise. Sounds like it could be the TPS, or possibly a failing shift solenoid or worn valve body. Fix it? I probably would, if I liked it as much as you seem like you do. It might run several thousand, but then again, new car payments over a year run more than that. Trade in potential is virtually nil because of the mileage, so at this point, I’d keep it. Why not?

[Anonymous]

Anonymous wrote:This might be the most helpful thread to the most people on DCUM ever. Thank you!

Wow, I didn’t realize the bar was so low haha. Thank you, though.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Hi. I have 2011 Mercedes ml350 4matic suv that has just over 200000 miles. When I go up hills and or accelerate at slower speeds (less than 40mph), the car stutters and kind of hesitates. A friend riding with me said it seems like a transmission issue. I haven’t taken it to the shop yet but how much more would you invest in a car with that type of mileage? The car has been pretty good to me. However, last year I spent $1000 to get A/C repaired (cracked compressor) $270 lift gate repair and $300 for window motor. I really wanted to keep it for my nearly 17 year old DD but I wondering should I just move on? I would love to move up to a 2015/2016 GL but my current mechanic thinks those are trash and constantly trying to talk me into buying a Honda Pilot or something Korean. Any recommendations or general thoughts?

Also wondering what are the service recommendations when car hits 200000 miles?
TIA!

Congrats on getting your car to 200K. Well done. I’ll admit I don’t know much about MB’s, they’re not my area of expertise. Sounds like it could be the TPS, or possibly a failing shift solenoid or worn valve body. Fix it? I probably would, if I liked it as much as you seem like you do. It might run several thousand, but then again, new car payments over a year run more than that. Trade in potential is virtually nil because of the mileage, so at this point, I’d keep it. Why not?

Thank you for replying back so quickly! Thanks for the advice.

So do you have a general service recommendations for 200000 milers?

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:What's the best way to buy a vehicle in good condition from the 80s?

From the 80’s? Probably at a classic car auction or a for sale ad on Hemming’s Motor News.

Pretty much the only cars still left from the 80’s are the “keepers”, that the owners specifically wanted to hold on to. That means they’ve been maintained, but also means they’ve lasted long enough that their value is starting to creep back up. Fox Body Mustangs, for example. You couldn’t give away a 1987 5.0 in the mid-2000’s. But now? One in decent shape will run more than it cost new in ‘87.

Thanks! I was looking for a 300-something Mercedes, maybe a wagon, unless you think that's a terrible idea. But I'll check out the mustang you mentioned.

Oh I’m not recommending the Mustang. I was just using it as an example. A car that sold for maybe $14k in 1989, lost much of its value by 2005, then with numbers reduced by attrition, the values started creeping up again to the point where good ones today are back to $15k or more.

I can’t tell you what classic 80’s to get, that’s entirely subjective. But look for something you’ll enjoy driving. Something you want to drive, versus something you have to drive.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Most of my driving during the week is to take the kids to and from school. It's 10 minutes there. 10 minutes off while I take them in side, then 10 minutes back. Twice a day. Based on your previous post, this isn't great for the car as it's not running long enough. Any suggestions, other than driving circles around my block and annoying my neighbors? We do get longer drives done on the weekends. It's an Audi 2.0 4-cylinder TFSI (turbo) engine if that makes a diffrence.

So in that sort of driving profile, a few things are happening. None are good.

1) your exhaust system is accumulating water inside it, and staying moist, which will eventually corrode it. Yours is made of stainless steel, but the muffler internals and catylist housing is mild steel. That will eventually rust. When gasoline is burned, the biggest by product of that combustion is water vapor. Ideally, the exhaust system will get hot enough during a drive to ensure that all that water stays in a gaseous state all the way out the exhaust system. But before it gets that hot, the rear parts of the system are still cool, and the water vapor condenses there. Unless you get the exhaust hot enough to boil off that water, it’ll have moisture in it.

2) the battery isn’t being charged enough by so litttle driving. You’re in a constantly descending charge state that will eventually not be able to start the car. Think of it like this- this is just a hypothetical, but accurate- let’s say it takes 10:30 of running to replace the electrical charge used to start the car. But you only drive 10:00. So each time, the battery gets :30 too little charge. Over time, that cumulative effect will slowly drain the battery

3) your engine oil isn’t getting hot enough to boil off the contaminants from the gasoline being burned. Same deal as the water in the exhaust, except it’s petroleum contaminants instead of water. Hot oil boils them off and sends it into the PCV system to be burned and disposed off in the exhaust.



Pick one day a week and drive for thirty minutes to an hour, ideally at highway speeds. Also, really get on the throttle aggressively and run it very hard a few times on these weekly drives. Plus, your car is a lot of fun. Go enjoy the performance.

Thanks for the advice. We do get 30+ minute highway drives usually once or twice a week.

The car has stop-start technology. Will that make it even worse since the engine is running maybe 8 minutes of a 10-minute drive? Bunch of stoplights so the engine turns off then.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Hi. I have 2011 Mercedes ml350 4matic suv that has just over 200000 miles. When I go up hills and or accelerate at slower speeds (less than 40mph), the car stutters and kind of hesitates. A friend riding with me said it seems like a transmission issue. I haven’t taken it to the shop yet but how much more would you invest in a car with that type of mileage? The car has been pretty good to me. However, last year I spent $1000 to get A/C repaired (cracked compressor) $270 lift gate repair and $300 for window motor. I really wanted to keep it for my nearly 17 year old DD but I wondering should I just move on? I would love to move up to a 2015/2016 GL but my current mechanic thinks those are trash and constantly trying to talk me into buying a Honda Pilot or something Korean. Any recommendations or general thoughts?

Also wondering what are the service recommendations when car hits 200000 miles?
TIA!

Congrats on getting your car to 200K. Well done. I’ll admit I don’t know much about MB’s, they’re not my area of expertise. Sounds like it could be the TPS, or possibly a failing shift solenoid or worn valve body. Fix it? I probably would, if I liked it as much as you seem like you do. It might run several thousand, but then again, new car payments over a year run more than that. Trade in potential is virtually nil because of the mileage, so at this point, I’d keep it. Why not?

Thank you for replying back so quickly! Thanks for the advice.

So do you have a general service recommendations for 200000 milers?

You’re doing it right already. Just keep doing it. A car with 200,000 miles is running a lot, and that’s actually good for vehicles. Highway miles are the absolute best for vehicle longevity, btw.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Most of my driving during the week is to take the kids to and from school. It's 10 minutes there. 10 minutes off while I take them in side, then 10 minutes back. Twice a day. Based on your previous post, this isn't great for the car as it's not running long enough. Any suggestions, other than driving circles around my block and annoying my neighbors? We do get longer drives done on the weekends. It's an Audi 2.0 4-cylinder TFSI (turbo) engine if that makes a diffrence.

So in that sort of driving profile, a few things are happening. None are good.

1) your exhaust system is accumulating water inside it, and staying moist, which will eventually corrode it. Yours is made of stainless steel, but the muffler internals and catylist housing is mild steel. That will eventually rust. When gasoline is burned, the biggest by product of that combustion is water vapor. Ideally, the exhaust system will get hot enough during a drive to ensure that all that water stays in a gaseous state all the way out the exhaust system. But before it gets that hot, the rear parts of the system are still cool, and the water vapor condenses there. Unless you get the exhaust hot enough to boil off that water, it’ll have moisture in it.

2) the battery isn’t being charged enough by so litttle driving. You’re in a constantly descending charge state that will eventually not be able to start the car. Think of it like this- this is just a hypothetical, but accurate- let’s say it takes 10:30 of running to replace the electrical charge used to start the car. But you only drive 10:00. So each time, the battery gets :30 too little charge. Over time, that cumulative effect will slowly drain the battery

3) your engine oil isn’t getting hot enough to boil off the contaminants from the gasoline being burned. Same deal as the water in the exhaust, except it’s petroleum contaminants instead of water. Hot oil boils them off and sends it into the PCV system to be burned and disposed off in the exhaust.



Pick one day a week and drive for thirty minutes to an hour, ideally at highway speeds. Also, really get on the throttle aggressively and run it very hard a few times on these weekly drives. Plus, your car is a lot of fun. Go enjoy the performance.

Thanks for the advice. We do get 30+ minute highway drives usually once or twice a week.

The car has stop-start technology. Will that make it even worse since the engine is running maybe 8 minutes of a 10-minute drive? Bunch of stoplights so the engine turns off then.

Yep. I’d consider hooking a battery charger up every month or so for a few hours or overnight, just to keep the battery up. You’ll prolong the life of your battery by probably a couple years.

[Anonymous]

Re: nitrogen in tires--my son put nitrogen in mine 2 years ago. Rotating is the only thing that has had to be done since, and I live where the difference between winter and summer can top 140 degrees.

Questions: why are universal symbols so hard to figure out? I wondered what the movie camera symbol meant (not a camera, it's the engine!) and the temp symbol always looks to me like a tiny sailboat on the waves. The tire symbol looks like a cross between calipers and a horseshoe.

[Anonymous]

Anonymous wrote:Re: nitrogen in tires--my son put nitrogen in mine 2 years ago. Rotating is the only thing that has had to be done since, and I live where the difference between winter and summer can top 140 degrees.

Questions: why are universal symbols so hard to figure out? I wondered what the movie camera symbol meant (not a camera, it's the engine!) and the temp symbol always looks to me like a tiny sailboat on the waves. The tire symbol looks like a cross between calipers and a horseshoe.

The engine light actually looks like a tiny little cartoon engine when viewed from the side. Which I guess also sorta resembles a movie camera, I guess. As for temp, it’s supposed to be a thermometer immersed in water (coolant) . But yeah, I guess is does sorta look like a little sailboat on waves. Maybe a bout with a flag on it, that’s even better. The tire pressure is the easy one. That’s the “>” symbol (low) followed by a U looking sympbol (more of an Omega actually) that is supposed to represent the cross-sectional view of a tire. For this one, thought they should use an “O” shape, with a flattened bottom, but that’s just me. I guess it’s like seeing animals shapes in clouds. You miss it, but when someone points it out, you’re like “oh yeah, now I see it!” Lastly, where the hell do you live where the temp is 140 degrees apart winter to summer? Because I wanna make sure I never accidentally go there!

[Anonymous]

Anonymous wrote:
how do you change the tires on a 1963 Dodge Dart?

in the 450sl how did they balance weight in rear of car?

What is purpose of STP and who developed it?

How many times it took to created WD40?

16.5” bias ply tubed tires? Or 16” with tubeless radials? Specifiy please.

The battery is in the trunk, IIRC. Why anyone is worried about F/R weight distribution in a soft-sprung convertible tourer driven by tennis wives is beyond me though.

STP was invented by Wayne LePard, the father of the kid down the block from me when I was growing up. I know this because he had an STP sticker on his 1965 Falcon hotrod. It was badass.

40 I suppose. Dunno, I dont use it much, since I’m not an electrician. Being that it’s mostly kerosene, it dissolves grease and oils that are currently in place, so it’s not a very good lubricant. Yeah, it makes the squeaking stop temporarily, but when it evaporates, there’s even less lubricant than before. I use it for cleaningg out water from wiring harnesses in flooded cars, but that about it.

The Dodge Dart had 13 inch rims. You remove lug nuts counter clockwise one side and clockwise other side. The 450sl in trunk opposite of battery has a hidden piece of concrete hidden to counterbalance weight of battery on opposite side of trunk

STP is Studerbacker Packard

WD - Water displacement was invented on 40th try


That’s really cool. I’m gonna file #1 and #2 away for the old guys I get coffee with. At least #1 anyway. #2, I might use that one for a Benzaphile if I ever meet one (doubtful since I don’t work on them).

You should report directly to Final Jeopardy!

[Anonymous]

Dear OP, thank you for all your good contribution here thus far.

I've seen some posts here about 10-min drives, car not warming up sufficiently and related consequences. I'm my case, I do a lot of short drives as well, approx 10 mins, but after around 3 mins (at least in this heat, takes longer in winter), the water/engine temperature needle is approx in the middle, indicating that engine has reached normal operating temperature. Now, for the remaining 7 minutes driving at normal operating temp, does that count as "regular" driving enough to (contribute to) get the water/vapors out of exhaust pipe, gasoline particles out of oil etc, or no?

[Anonymous]

I have a sports car that I drive rarely (mainly because it's a 2-seater and we have 2 small kids), like less than 1,000 miles/year and it may go weeks between uses. I keep it on a battery tender. How will I know the battery is finally ready to give up? I think the battery is 10 years old, but it's _always_ been on a tender unless I'm driving it.